A: You can connect the sub-out port on your speaker to Subwoofer input. If your speaker does not have sub-out port you can connect your source to T5 then connect the audio out to your speaker.

A: No, you can't connect to existing 2.1 speaker system. T5 only can connect to sub-out port on speakers or directly to your audio source.

A: Press and hold the volume knob for approx. 8-10 seconds to clear Bluetooth Pairing. then you can pair with your phone/device.